feat(cxx_extractor): better error when opening KzipWriter

[ivucica]

Add the path to the kzip file to the error message when it fails to open.

When using runextractor compdb from compile_commands.json generated with refresh_compile_commands under Bazel 6.5.x with default system GCC-based toolchain, extractions seem to be reporting en-masse that ALREADY_EXISTS: File already exists, but it is difficult to know what file is being written to.

This makes it easier to triage why this is happening.

[ivucica]

Does not seem to build for unrelated reasons: https://app.buildbuddy.io/invocation/3870d3f7-df29-4fa6-9c42-6ba10f2a0948#log

With -k flag: https://app.buildbuddy.io/invocation/bac95580-79cc-40f0-8c13-621d0bbd165b

In short, it looks like external workspaces for LLVM and protobuf are failing to build badly.

[ivucica]

(Locally I have Clang+LLVM 16 installed, and not from source code. I've run the build with Bazelisk, which pulled in Bazel 7.1.0. Beyond that, I don't know why the external repos would not be fetched correctly.)

[ivucica]

Really strange:

$ bazel build @@llvm-project//llvm:Demangle
INFO: Analyzed target @@llvm-project//llvm:Demangle (0 packages loaded, 0 targets configured).
ERROR: /tmp/bazel/_bazel_ivucica/be7e2977d85a195914402eddda107797/external/llvm-project/llvm/BUILD.bazel:188:11: Compiling llvm/lib/Demangle/MicrosoftDemangle.cpp failed: (Exit 1): clang failed: error executing CppCompile command (from target @@llvm-project//llvm:Demangle) /usr/lib/llvm-16/bin/clang -U_FORTIFY_SOURCE -fstack-protector -Wall -Wthread-safety -Wself-assign -Wunused-but-set-parameter -Wno-free-nonheap-object -fcolor-diagnostics -fno-omit-frame-pointer ... (remaining 71 arguments skipped)

Use --sandbox_debug to see verbose messages from the sandbox and retain the sandbox build root for debugging
clang: error: no such file or directory: 'external/llvm-project/llvm/lib/Demangle/MicrosoftDemangle.cpp'
clang: error: no input files
Target @@llvm-project//llvm:Demangle failed to build
Use --verbose_failures to see the command lines of failed build steps.
INFO: Elapsed time: 0.138s, Critical Path: 0.03s
INFO: 9 processes: 9 internal.
ERROR: Build did NOT complete successfully

$ sha256sum bazel-kythe/external/llvm-project/llvm/lib/Demangle/MicrosoftDemangle.cpp 
9270a17386ea0c069d54628d0fabbc0681837d2e0860bf66dedb9f40b3da4ef5  bazel-kythe/external/llvm-project/llvm/lib/Demangle/MicrosoftDemangle.cpp

It could be something I haven't yet tried to learn about Bazel modules -- because the repo seems to have been fetched in full.